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171.
A systemic graft-versus-host reaction (GVHR) leading to 50% mortality by day 20 was elicited by the injection of CBA (105) or B10 (106) parental T lymphocytes into irradiated (750 rad) and bone marrow protected (CBA x B10)F1 recipients. Between days 12 and 28 the spleens of the sick mice were analyzed by limiting dilution, performed with irradiated F1 cells and a source of interleukin-2 (IL-2), to determine the frequency of cells with an antihost proliferative or cytolytic activity and to derive T lymphocyte clones. The frequency of cells with antihost proliferative or cytolytic activity was approximately 10–3 in either combination. In the CBA vs F1 GVHR, all eight clones isolated with anti-F1 activity were Lyt-2, noncytolytic, mixed lymphocyte reaction (MLR) responders and IL-2 producers, three of which mapped to the A b locus, while in the B10 anti-F1 combination, eight of the nine anti-F1 clones isolated were Lyt-2+, poor MLR responders and non-IL-2 producers, but cytolytic and mapping to K k . These findings suggest a much higher frequency of T cells recognizing the A-locus antigens in the CBA than in the B10 strain.  相似文献   
172.
Abstract Pseudomonas aeruginosa possesses a peptidase N activity analogous to those described in Escherichia coli and Salmonella typhimurium . This activity resides in a protein with an M r value of 85 000. Part of this peptidase activity appears to be associated with the cytoplasmic membrane. The K M value for this peptidase bound to the cytoplasmic membrane is in the range of 0.5 mM.  相似文献   
173.
Summary The aim of the present study on the fetal porcine pituitary was (1) to detect by means of the immunoperoxidase technique the earliest stages of cells producing polypeptide hormones: -MSH, ACTH, -LPH, - and -endorphin, growth hormone (GH) and prolactin (PRL), (2) to study the development of the synthesis and the storage of these hormones during fetal life, and (3) to detect whether several hormones can be located in one and the same cell.The corticotropic cells were revealed as the earliest functional elements of the fetal anterior pituitary. Our results indicate clearly that ACTH, -MSH, -LPH, - and -endorphin appear at 34 days in the same regular, round or ovoid cells; no differences in the time of their appearance could be observed. The ACTH-cells, irregular or angular in shape and endowed with cytoplasmic processes such as described in the adult pituitary, were not seen until day 50. The first GH-cells were detected between 40 to 45 days of fetal life. From day 45 to 90, the GH-cells greatly increased in number and in staining intensity of their progressively extending cytoplasmic area, but they displayed the same regular and round shape. The PRL-cells were the last cell type to appear in the fetal pituitary. The first PRL-cells, small in size and round or ovoid in shape with a high nucleus/cytoplasm ratio, were detected at day 70. At day 80, the PRL-cells increased in size and staining intensity. They displayed an irregular elongated or stellated shape and cytoplasmic processes resembling those characteristic of the adult pituitary. These data suggest that in the fetal porcine pituitary: (1) ACTH, -LPH and related peptides are synthesized and stored in the same cells, and (2) PRL and GH appear in individual cellular elements.  相似文献   
174.
Del11p13/nephroblastoma without aniridia   总被引:6,自引:0,他引:6  
Summary A patient is reported with del11p13, low catalase level, nephroblastoma, chordee and cryptorchidism, no evident mental retardation, and with normal irides. This unique observation suggests the following order of loci in 11p13, from centromere to telomere: catalase, Wilms tumor, aniridia. The chromosomal origin of nephroblastoma may be more frequent than estimated on the basis of its association with aniridia.  相似文献   
175.
Summary Observations in a family point to the existence of autosomal dominant inheritance for discrete subaortic stenosis (DSS), which made up part of a multisystem disorder. Both parents, offspring of two full siblings, had short stature, obstructive lung disease (OLD), hoarseness and upturned nose. The father alone had aortic stenosis and inguinal hernia.The six offspring, aged from 13 to 28 years, were followed up for up to 8 years. While one of them was virtually normal, and one had only minor abnormalities, four siblings displayed clinical signs of progressive aortic stenosis. Of the two eldest siblings who eventually died, necropsy in one showed a discrete subaortic stenosis, which was hemodynamically proven in one and surgically corrected in another sibling.Upturned nose was present in each examined member of the family, short stature and hoarseness in five of the siblings, DSS in four, OLD, inguinal hernia and congested episcleral veins in three, kyphoscoliosis in two, while epicanthus, strabismus, microphthalmos and widely spaced teeth were noted in the deceased female. The prevalence of some of these traits in roughly three-quarters of the sibship was consistent with an underlying single gene abnormality in affected heterozygous parents. We proposed that this constitutes a new syndrome.  相似文献   
176.
Summary The caudal spinal cord of Eigenmannia virescens is not enclosed in a neural canal of the vertebral column. In fact, a segmented vertebral column with neural and ventral arches is lacking and replaced by a non-segmented baton-like bony structure on which the free spinal cord is located. The baton consists of calcified bone tissue with bone cells. Individual differences exist as far as the length of the rod is concerned. The electromotor neurons of this caudal part of the spinal cord are histochemically acetylcholinesterase-positive. The electrocytes which surround this part of the spinal cord show strong enzymatic actitivity on the posterior innervated face. However, there is also activity on the non-innervated lateral and anterior faces.  相似文献   
177.
Peanut agglutinin (PNA), a lectin specific for terminal d-galactosyl residues, was found to react with embryonal carcinoma cells, but not with their differentiated derivatives. Receptors for PNA were detectable at the surface of all cells of the quasinullipotent F9 line and on only 50% of the multipotent PCC3/A/1 line. The fraction of the PCC3/A/1 population which expresses the F9 antigen was found to be included in the subpopulation carrying the PNA receptors. PNA+ and PNA? subpopulations of PCC3/A/1 were separated by a PNA-mediated reversible agglutination of PNA+ cells with rabbit erythrocytes. These subpopulations were essentially F9+ and F9?, respectively.  相似文献   
178.
179.
The discovery of Foraminifera and Ostracodesin the dark green, sandy-glauconitic marl clay in the Joux Valley (in the Vaudois Jura) suggests to date these sediments Middle and Upper Albian. The Ostracode associations are similar to those found in the Paris Basin, but different from those which characterize the subalpine region.  相似文献   
180.
Summary A microcalorimetric study is proposed to follow the degradation of straw by a mixed bacterial culture. The effect of an alkali pretreatment of straw is described.  相似文献   
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